Internal grinder



March 19, 1929. w, L, BRYA 1,705,749

I NTERNAL- GR'E NDER Fiied Dec. 29. 1921 5 Sheets-Sheet L Mach 19,1929. I w, L, BRYANT 1,705,749

INTERNAL GRINDER Filed Dec. 29. 1921 5 Sheets-Sheet 3 March 19, 1929. w. 1.. BRYANT INTERNAL GRINDER Filed Dc. 29. 1921 5 Sheets-Sheet March 19, 1929. w. L. BRYANT INTERNAL GRINDER Filed Dec 29. 1921 S Sheets-Sheet 5 diminished.

Patented Mar. 19, 1929..

1,705,749 PATENT QFFICE.

WILLIAM 1.. BRYANT, or srnrnerrnrinfvnnmonr.

INTERNAL GRINDER.

Application filed December 29, 1921. SeriaI'No'. 525,537.

This invention relates to grinding machines of that type designed for grinding internal surfaces and has been designed more particularly for grinding the internal faces of ball bearing raceways and analogous structures. While many of the novel features of this machine might be otherwise advantageously incorporated, it has been found convenient to embody them in a machine of the vertical spindle type.

One of the features of this invention comprises a plate-like work holder rotatably carried by the machine and having an opening through which the shaft of the grinder wheel or lap passes, the grinding shaft being positioned vertically. This plate is constructed so that it is only necessary to lay it in proper position, preferably on a ball bearing, the upp'errace of which is carried thereby, its weight retaining it in position without the requirement of any devices specifically for this purpose. The work holder is thus gaged for accuracy of rotation by its side face which rests on the bearings and at points spaced from the axis of rotation of the work considerably further than the surface to be ground which extends in the direction of this axis. The work holder is thus mounted quite independent of the mounting of the grinding wheel in the machine frame and is gaged for accuracyin-a plane perpendicular to its rotation axis. This plane is adjacent to the central radial plane of the surface to be ground, the distance between such planes being less than the radius of the bearing engagement of the work holder, whereb the effect to vary angularly the axis' 1f the surface to be ground of any uneven wear or unavoidable irregularity in the bearing surface will be This work support is rotated by a gearwhich engages peripheral teeth thereon, the lines of engagement between the meshing teeth being parallel to the axis of rotation so-as to minimize interference with theautomatic determination of the axis of rotation of thework by its gravity maintained bearing engagement. This is'an iniportant' feature as it gives great stability for the support of the work making for ex-.

treme accuracy of, the grinding operation.

A further feature resides in the construction and mounting of the grinder shaft by which a traversing axial motion is effected during the operation of the machine and by which it is retracted axially from the work when the rotation of the work holder is stopped. It. is therefore a simple matter to stop the movement of the work and retract the wheel from operative relation thereto for ready inspection or removal of the work.

A still further feature relates to grinder. wheel drive mechanism in a unit independent of other mechanisms.

Yet another feature relatesto the mechanism for imparting a relative cutting feed transverse to the direction of traverse between the grinder and the work in which there is no possibility of lost motion and by which an exceedingly accurate adjustment is ossible. I

therffeatures of this invention relate to lubrication of the machine.

Furtherfeatures and advantageous details and combinations of parts will appear from a more complete description of an embodient of the invention disclosed in the accom panying drawings in which Figure 1 is a front elevation of the machine.

Figure 2 is a plan view.

Figure 3 is a section on line 33 ure 2. I

Figure 4 is a section through the upper part of the machine corresponding to a portion of Figure 3 illustrating a modification. Figure 5 is a section on line 55 of of Fig- 'Figure 3.

Figure 6 is a section on line'6-6 of Figure 3.

Figure 7 is a vertical section through'a portion of the grinding wheel shaft and its mounting substantially on line 77 of Figures Sand 9.

Figure 8 is a section on line 8 8 of Figure 7.

Figure 9 is a section on line 99 of Figure 7 The machine comprises a box-like stationary casing indicated at 1 having a central opening through its forward .face adapted to 100 be covered by a-hinged door 2. Within the lower portion of this casing apart-ition '3' shown in Figures 3, 5, and 6 defines a reservoir for a cooling fluid. Adjacent the inner side of the partition 3 is a bearing 4 m les which isslidably mounted a vertical plunger 5. This plunger extends upwardly through the machine being guided near its upper end in a bearing 6 and projects upwardly through a cylindrical portion 7 upstanding 110 from the central portion of the casing 1.

casing 9 serves tohouse the work and the grinding wheel. This casing has a flat annular base 11 extending inwardly from the walls of thecylindrical portion 7 and terminating on its inner face in an upstanding flange 12. It also has a circular flange 13 concentric with the flange 12 and within this flange 12 is located the outer ring 14 of a ball bearing. On its upper face flange 13 carries a ring 15- of a second ball bearing raceway. Raceway rings 16 and 17 mating rings .14 and 15, respectively support an annular work-holding plate 18 which may be seated in the machine and be retained in position by its weight. The position of the plate is thus gaged directly from its lower face which rests on the ball bearings on a rigid support" and in a plane perpendicular to its axis of rotation and is quite independent in its mounting from the grinding wheel mounting which will presently be described. This plate 18 has an annular flange 19 positioned within the flange 12 and carries a ring member ,20 to which the work to be.

ground shownat Wmay be clamped by clamping plates 21 made fast by the bolts 22. Preferably also the work plate 18 has a depending marginal flange 23 extending outthe covers .25 and wardly of the flange 13 andcarrying on its lower edge gear ,teeth 24 by which the plate:

may be rotated. The upper face of the plate 18 has fixed thereto an annular cover member 25 which overlaps a cover member 26 made fastto the casing member 9. This cover plate prevents cooling fluid from find-- ing its way inside of the casing member and outwardly of the work plate but by removing 26 it is evident that the work plate 18 may be lifted out of the machine, the two sets, of ball bearings merely guiding and supporting the plate laterally and vertically.

At one side the casing member 9 is extended to forma housing'27 for a driving pinion 28. meshin with the teeth 24 on'the work plate. This driving pinion has an annular recess .29 on its lower face within which engages an upstanding annular flange 30 on the casing 9. This pinion is made fast 33 extending outwardly from the cylindrical portion 7. The shaft 31 beneath the bracket 33 has journaled thereon a belt pulley 34. Beneath this belt pulley is positioned a I clutch wheel 35 slidable axially of the shaft 31 and keyed to rotate therewith. This clutch is normally urged into engagement with a mating surface on the pulley 34 by means of a plurality of spring-pressed pins 36 seated in sockets in the hub 37 of the .clptch which engage on the upper surface of the collar 38 made fast to the shaft 31. The

hub 37 is flanged at 39 at its lower end and riding on this flange, at diametrically opposite points,.is a pair of shoes 40 which are carried at the ends of'a pair of arms 41 of a lever 42 carried by a rock shaft journaled in lugs 43 depending from the top of the easin '1. By pressing'upwardly on the outer en of arm 44 of this lever, it is evident that the shoes engaging the flange 39 depress the clutch Wheel 35 to disconnect it from the pulley 34. Threaded through the outer end of the arm 44 is an adjusting stud 45 having a knurled thumb nut 46 threaded on its upper end and normally bearing on the upper face of the casing 1 through a perforation in which the stud passes. termines the extent to which the stud 45"shall project below the arm 44.

' The shaft 31 is seated at its lower end in a ball step bearing 50 and above this step bearing carries a worm 51. This worm meshes with a worm wheel 52 fixed to a' transverse shaft 53 journaled in a bracket member 54 extending inwardly from the easing. This bracket also furnishes'the support of the step: bearing 50. The shaft 53 has fixed thereon between its ends an eccentric 55 which fits a bearing opening. in theend of a lever 57. This lever is fulcrumed at 58 between jaws 59 at the upper end of a link 60 which is pivoted at its lower endto a lever 61 madefast to a rock shaft 62 ext-ending outwardly of the casing and having fixed at its outer end a, hand lever 63. This hand lever extends upwardly along the front of the machine, as shown in Figure 1, and termimates in a handle 64 having slidable therein a spring-pressed latch member 65 which may lower end, and a portion of the bracket 55.'

The upper end of this rod 72 is positioned directly beneath the stud 45 so'that rocking the lever 63 to the right, as shown in Figure 1, the fulcrum of the lever 57 is lowered, thus lowering its outer end about the eccentric 55 as a pivot and the rod 72 is raised, impinging on the stud 45 and lowering the clutch member 35 from engagement with the pulley 34. At the same time therefore that the outer end of the lever 57 is lowered by movement of the hand lever 63, the driving connection to rotate the work holder '18 is disconnected.- This lever 57 actuates the grinding tool in a manner to be described, removing it fronroperative relation tothe work holder 18.

The plunger mechanism 5 comprises an and 8 and an intermediate section 81 and a lower section 82. The upper section 80 is formed as a sleeve having an eccentric bore 84 longitudinally thereof. A sleeve 85 is threaded therein at its upper end at 83, and carries at opposite ends outer race members 86 of a series of ball bearings. The inner race members 87 are carried by reduced portions 88 of a vertically extending grinder wheel shaftor spindle 89 carrying a grinder wheel 96 at its upper end.

Above the upper bearing member this shaft carries a ring- 90 having a marginal depending flange 91 surrounding a plug sleeve 92 to prevent'the entrance of water or other material to the bearings. The collar or ring 90.may be retained in position by a lock nut 95 engaging a threaded portion on the spindle '89. The bearings are accessible from the a per end of the sleeve 85 by removal of the plug 92 which is threaded injits upper end. To take up wear of the bearings, race members 86 may be formed tapered anda collar 97 internally threaded in sleeve 85 may be urged against the lower member 86 to wedge the balls inwardly by means of a torsion coil spring 98, engaging at opposite ends with collar 97 and sleeve 85. The upper end of sleeve '85 terminates in a flange 93 which extends over the upper end of the section 80 and has openings 94 for the reception of a spanner wrench by which the sleeve 85 may be screwed into and out of the section 80.

The upper end of the section 80 is rovided with a shield or apron 100 forme with 2. depending marginal flange 101 to direct the cooling liquid adjacent the inner walls of the cylindrical portion 7 and outwardly of the bearing 6, where an annular channel 102 (see Fi ure 3) is formed to receive it. From this channel the cooling liquid passes through a passage 103 in the casing 1 as shown in Figures 2, 5 and 6 into the chamber or'tank 104 formed between the wall 3 and an outercasing wall 106.

The upper and intermediate sections 80 and 81 may be formed integral, if desired, the intermediate section 81 being centrally enlargedand having a chamber therein at 110 in which is housed a high speed electric motor 111. This motor has an armature shaft 112 which extends upwardly within a ball bearing113 and'has fixed at its upper end a universal joint 114 to the upper member 115 of which is fixed the lower end of the spindle 89. The lower end ofthe shaft 112 is mounted in a ball step bearing 116 in a block 117 closing the lower end of the opening 110. At 118 are shown ventilating openings through the section 81 for the purposes of ventilating the motor and through which electrical conductors may be passed. The lower end of the section 81 terminates in an outwardly extending flange 120 which imparts axial motion to the plunger 82, this axial motion being imparted during the operation of the machine by the rocking of this lever about the fulcrum 58 by means of the eccentric 55. This vertical motion of the grinding wheel is of comparatively small amplitude, but gives a traverse of the wheel relative to the work and may properly be termed a vibratory movement. Axial motion of the plunger is also produced by moving the hand lever 63, this -motion being suflicient. when the lever is carried to its extreme right hand osition as shown in Figure 1 to depress t e grinder wheel out of cooperative relation with the work held on the work plate 18. When this action takes place, however, the rotation of the, work plate stops as before described. With this construction it is easy to sto the rotation of the work and depress t e grinder wheel forthe removal ofthe work or measurement or inspection thereof without stopping the rotation of the wheel and without danger of injury being done thereby.

The plunger is normally urged toward its 127 made'fast-to the lower end of a cable 128 which passes over a guide pulley 129 rotatingthe plunger within its bearings 4;

upper position by means of a counterweight about an axis eccentric to its own axis by I and 6. The grinder wheel will then be moved bodilyin an arcuate path about an axis eccentric to the axis of-rotati n of the work. This action is made use 0 to feed the wheel into the work since this movement causes a relative change of position between the wheel andthe work tovary its eccentricity to the axis of the work. This feed motion is produced by means of an arm 132 made in two sections clamped by means of bolts 133 to the upper section 80. The outer end of this arm 132 is formed as a gear seg-. 'ment 134 which meshes with a long pinion 135 carried by a vertically extending shaft 136. This shaft is carried'in a bearing 137 at its lowen end mounted for slight rocking movement'in the bracket 138 extending inwardlyfrom the wall of the casing 1. The bearing 137 is held in position by means of a screw 139 which is screwed into the bracket 138- and which has a pin 140 engaging in an opening in the bearing137. The upper end of the shaft 136 is supported in a floating bearing 140, This bearing ispositioned inan openin in a wall 141 of the casing 1 and is urged in directions at right. angles to eaehiotherl .by a pair. of spring-pressed pins. 142 seated in ockets in the portion 141,.

the action of t esepins being resisted by adjusting screws143 positioned opposite thereto in the wall 141- and bearing against I the memberi1'46. The upper end of the shaft 136 has keyed thereto a worm wheel 137 which mmhes with a worm 138 carried.

- by a shaft 139' which extends to the front ofthe machine as shown in Figures 1 and 2, and which is actuated-by any suitable feed preferably of the ratchet type indicated gen- .j orally at 150. By adjustment of the screws .143 the worm wheel may be adjusted relative to the worm to take-up wear and to insure against lost motion between these parts. Backlash between the gear segment 134 and the pinion 135 is prevented by means of a counterweight 144 attachedto a cable 145 extending over a guide pulley 146 partly sur- "rounding the .plunger section 81 and made fast thereto by abolt 147 (see Figure This'cOHHterWeightcauSes a constant turning effort to be exerted on the plunger to urge the segment against the teeth of the pinion 135. This pinion is made long so that the plunger reciprocates either in the normal running of the machine or when it is further depressedwhen it' is desired to inspect or remove the work, without becoming disengaged therefrom. a

The rotation of the work-holding plate may be effected from a drive shaft 160 positioned at the back of the machine (Figure 2 having a belt wheel 161- thereon from tends about the belt I also, by means of a belt pulley 165 and idlers which a belt-162 passing over idlers 163 expulley 34. This shaft 166, drives a pulley 167 of the cooler circulating pump 168. By means of this pump the cooling liquid is pumped through a pipe 169 (see Figure 3) by which it is conducted to any suitable point over the grinding wheel.

If desired, the vertical actuation of the wheel-carrying plunger may be-utilized to lubricate thebeari-ngs. For this purpose in Figure 3 is'shown a receptacle or well 170 positioned below the end-of the plunger.

. From this well oil supply pipes as 171 and 172 may extend to the various bearings, as

' formed through t shown, the pipe 171 extending to the bearin 50 and following upwardly therethrough and into a shallow basin 173 formed "on the brac et 54 within which the worm wheel 52 dips, the pipe 172 conducting lubricant to a basin 174 formed on the upper face of the partition member 141' in which the worm.

138 dips. Passagfways 175 may also be e plunger leading to the various bearings for shaft 89 as deired. ther pipes or passageways may be utilized memes in the samemanner to conduct the lubricant to an% point desired.

In igure 4 is shown a slightly modified construction of work plate in which a single ball bearing is employed to-take both lateral and vertical. thrust. This ball bearing is indicated at 178, the work holder 180 having a marginal flange 230 depending therefrom and having gear teeth 240 thereon meshing with the pinion 280. The plate 180 also has a smaller flange 231 extending over .a

slightly smaller flange 232' carried by the casing 260 to form'a labyrinth to prevent the flow of cooling fluid to the gear teeth or to the bearings. A cap plate 250 of slightly difi'erent form is also shown at the top of the casing, as in certain cases it might not be desirable to rely wholly on the weight of the parts to hold the work holder in operative position. Figure 4 also shows the use of gibs forthis purpose.

of anti-friction bearin metal such as bronze which may be ad1l1St8d toward and from the work holder by a screw 291 threaded through the cap plate 250 and being provided, if desired, with a lock nut 292. This construction insures against ac-' cidental displacement of the work holder from any cause and also makes it possible to use this type of holder on 'a horizontal machine.

ments of this invention, it'is evident that .various modifications and changes might be made therein without departing from. the

Each gib as shown comprises a segmental shoe 290, preferably Having thus described certain embodispirit or scope of the invention as defined of said. lever to rock-"said lever about said.

eccentric and move said plunger to remove. said wheel from operative relation to the work carried by said-holder.

2. A machine of the class described comprising a vertically movable plunger, a vertical. shaft journaled. in said plunger, a grinding wheel carried by the upper end of said shaft, an annular work holder for supporting work in operative relation to said wheel, means for rotating said work holder, a shaft, an eccentric on said shaft, 'a lever engaging said eccentric at one end and said plunger at'the other end, means actuated by said work-holder rotating means for rotattacle into which one end of said plunger ex tends, a tool shaft mounted 'in ball bearings in said plunger, a tool on said shaft, a work holder for holding work in operative relation to said tool when said plunger is partially retracted from said receptacle, means for moving said plunger axially to movesaid tool into and out of operative position, and means for'conducting lubricant from said receptacle to said ball hearings on movement of said plunger into said receptacle to move said tool out of operative position.

.4. In a machine of the class described, an axially movable plunger, a lubricant receptacle into which one end of said plunger extends, a tool shaft journaled in said plunger, a tool on said shaft, a work holder for holding work in operative relation to said tool when said plunger is partially retracted from said receptacle, associated mechanism, a lubricant receiving basin into which a portion of said mechanism extends, and means for conducting lubricant from said receptacle to said basin on movement of said plunger into said receptacle to move said tool out of operative position.

5. In a machine of the class described, an axially movable plunger, a lubricant receptacle into which one end of said plunger extends, a tool shaft mounted in ball bearings in said plunger, a tool on said shaft,

a work holder for holding work in operasignature.

tive relation to said tool when said plunger is partially retracted from said receptacle,

associated mechanisms, lubricantreceiving basins into which portions of said mechanisms extend, and means for conducting lubricant from said receptacle to said ball bearings and to said basins on movement of said plunger into said receptacle to'move said tool out of operative position.

6. A machine for grinding a cylindrical surface comprising a vertical grinder spindle, a stationary horizontal annular supporting frame surrounding such spindle,

an annular work support rotatable about an axis eccentric to that of the. grinder spindle, and of a diameter greater than that of the cylindrical surface to be ground, to afford a larger traveling annular bearing engagement, maintained by gravity, upon said frame; the plane of such bearing engagement being adjacent to the central radial plane of the cylindrical surface to be ground, the distance between such planes being less than the radius of such bearing engagement; whereby. the effect to var angularly the axis of the cylindrical sur ace to be ground, of any uneven wear or unavoidable irregularity in the bearing surface will be diminished.

7. A machine such as defined in the preceding claim, comprising means for rotating the work support, the lines of engagement of which with the latter are parallel to its axis of rotation to minimize interference with the automatic determination of the axis of rotation of the work by its gravity maintained bearing engagement.

In testimony where f I have aflixed my WILLIAM L. BRYANT. 

